1. Field of the Invention
The present invention relates generally to cutting elements used with a machine for cutting and clearing such things as brush, debris and small-diameter trees. More particularly, though not exclusively, the present invention relates to a free-swinging cutter having a particular configuration that enhances its cutting efficiency without retarding chip flow.
2. Problems in the Art
Land clearing devices, also referred to as forestry shredders, are used to clear such things as utility and pipeline right-of-ways, fire lanes, construction and development sites, and recreational sites. Many prior art forestry shredders have a plurality of cutting elements or cutters swingably mounted near the periphery of a horizontal drum. In response to the rotation of the drum, the cutters engage and cut through the tree or other woody debris. The shredded material is then discharged and left to mulch to retard erosion and decompose. Typically, the drum is mounted on and driven by a heavy-duty, full-time, four-wheel drive tractor.
During the cutting operation, each cutter strikes the target and then is pushed back somewhat, but then swings forward to the correct position for the next impact during the next revolution of the drum. The leading face of the cutter has a cutting edge which impacts the wood or other debris. As the cutter passes through the cutting area, the bottom surface of the cutter tends to remain in contact with the wood, creating additional drag which diminishes the efficiency of the cutting device. It is therefore desirable to provide a relief heel on the cutter such that the cutting edge extends below the rearward face of the cutter when the cutter extends radially from the drum.
A typical cutter is machined from a flat metal plate which is bent or curved into a generally stirrup-shaped member. This is a fairly fast and inexpensive manufacturing process. Manufacturing a cutter having a relief heel, however, requires additional machine and rework operations and is a more extensive process. One solution to the problem is to simply dimple the bottom surface near the rearward face of the cutter so that it is elevated above the cutting edge. Although this design is able to utilize a flat, generally rectangular plate, the dimpled portion tends to retard chip flow through the cutter between its sidewalls. Thus, there is a need in the art for an improved cutter that can be inexpensively manufactured with a relief heel from a simple rectangular plate without significantly retarding chip flow through the cutter.